1. Field of the Invention
This invention relates to a reinforcing tape or reinforcing sheet material to be attached to the end portion of a fastener tape which is intended for allowing attachment of a pin-and-socket separator.
2. Description of the Prior Art
The reinforcing tapes to be attached to the end portions of fastener tapes have been heretofore known in various types. The conventional reinforcing tapes include those which, for the sake of obviating the necessity of preparing reinforcing tapes dyed specially in various colors matched to the colors of dyed fastener tapes and consequently saving such time and labor as would otherwise be incurred in the inventory control, use transparent synthetic resin films in a superposed manner so as to show the colors of the dyed fastener tapes therethrough. For example, the reinforcing piece which is formed of two superposed transparent synthetic resin films having different melting points and is adapted to be applied fast to a fastener tape by melting that of the two films having a lower melting point as disclosed in Japanese Utility Model Publication No. (hereinafter referred to briefly as "JUM-B-") 44-25,843 and the lateral application tape which is formed by superposing on one side of a transparent film of nylon 6 or nylon 66 a transparent polyester copolymer film having a melting point of not more than 200.degree. C. so as to show the color of the base fabric of the fastener tape therethrough as disclosed in published Japanese Patent Application, KOKAI (Early Publication) No. (hereinafter referred to briefly as "JP-A-") 62-149,780 have been known to the art.
Since the reinforcing tapes formed of two layers of synthetic resin film as are disclosed in JUM-B-44-25,843 and JP-A-62-149,780 mentioned above are hard from the material point of view, they cannot be easily shaped by bending in conformity with the shape of the core portion of the fastener tape intended for permitting attachment of a pin-and-socket separator and, for this reason, the core portion of the fastener tape is not easily formed accurately in contour thereof. Further, these reinforcing tapes have the problem that when they are repeatedly bent, the bent lines thereof ultimately cause whitening possibly to the extent of jeopardizing the appearance of the reinforcing tapes.
To solve such problems, JP-A-8-299,033 filed by the assignee of this application proposes a reinforcing tape using a transparent polyester elastomer film as a surface layer and having an adhesive layer superposed on the reverse side thereof.